The present invention relates to a reversible cutting plate with at least two separate, similar cutting edges for cutting tools having a cuttin bit holder with adjustment surfaces in three spatial planes for the identically oriented supporting of bearing faces in at least two reset cutting positions of the reversing-symmetrical cutting bit which is at right angles to the cutting movement direction, the cutting edges being provided in in each case the same geometrical arrangement to the associated bearing face in such a way that the particular cutting edge in the associated reset cutting position is in the same dimensionally stable position relative to the cutting bit holder as at least one further cutting edge in the reset cutting position associated therewith, the cutting edges being provided at the ends of projections of a plate-like body, whose surfaces and edge faces form the bearing faces.
Reversible cutting bits of the aforementioned type are known, in which the projections, which at the end in each case form a cutting edge, which project from the body either in a straight line or laterally reciprocally displaced in opposite directions. In the first case, a linear elongated cutting bit is obtained, whilst in the second case the latter is double-angular in elevation. In both cases the projection which is not in the cutting attachment projects in the opposite direction to the projection in said cutting attachment and in this direction requires adequate space for the housing thereof. Particularly in the case of cutting processes taking place under confined space conditions, such as e.g. during profile turning, thread cutting, producing recesses and surface turning in narrow bores or ring channels, the smaller the dimensions of the parts to be worked, the more difficult the working, because the spatial extension of the cutting bit and/or cutting bit holder place limits thereon. For example, if an inner face is to be turned and the projections of the reversible cutting bit project in opposite directions, then the smallest internal diameter which can still be turned with said cutting bit is larger than the spacing between the cutting edges of the reversible cutting bit. In practice, it has been found that the smallest internal diameter which can be worked with the known reversible cutting bits is approximately 20 mm. A further disadvantage of the known construction is that the cutting edge which is not in the cutting attachment is located on the same surface as the cutting edge in the cutting attachment, so that the particular cutting edge which is not in use is unprotected and is exposed to influences which could cause damage.